Dye.



rates is filtered ofi. To produce the coloring fully the followingexample is given, the parts being by wei ht:--A. mixture 0f'8.2

UNITED STATES PATENT OFFICE.

MAX WEILER, OF ELBEBFELD, GERMANY, ASSIGNOR T0 FARBENFABBIKEN'VORM.FRIEDR. BAYER 8c (20., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

DYE.

976,417. No Drawing.

To all whom 'it may concern:

Be it known that I, MAx WEILER, doctor of philosophy, chemist, citizenof the Ger man Empire, residing at Elberfeld, Germany, have invented newand useful Imrovements' in New Dye, of which the folowing is aspecification. l r

This invention relates to the manufacture and production of new'dyestuifs which are obtained by condensing formaurin-di-ca'r-- boxylicacids with aromatic amins and oxidizing the leuco compounds thusobtained.

' The new dyes are dark powders soluble in dilute caustic soda lyegenerally with a red dish color.

The red to blue dyeings produced with the new (1 estuifscan be-treatedon the fiber with b1chromates, i fast shades being thus obt'ained.

In order to illustrate the new process more parts ofdimethylormaurin-di-carboxylic acid, (obtainable from.methylene-di-orthocresotinic acid), 4 partsofdiethylanilin and 100 parts.of glacial acetic acid is heated to 100 C. until a sample is no longercolored red by-the addition of caustic soda lye. The

productof the reaction is poured; into ice water and the leuco compoundwhich sepamatter, this leuco compound is dried, then dissolved instrongsulfuric :acid and these- .lution while being-stirred is oxidizedat 30 to 40 C. with nitrosyl sulfuric acid. When the oxidation isfinished the melt is poured Specification of Letters Patent.

Application filed June 21, 1910. Serial No. 568,102.

Patented Nunez, 1910.

Jon ice and the dye is filtered ofil 1t dyes wool in violet shades whichafter treatment with bichromates change into a dark violet. The dye canalso be dyed on chromed wool or dyed on wool together with the chromemordant.

Formaurin-di-carboxylic acid gives analogous results.

Other amins can 'be used, c. g. dimethylanilin, ethyl-benzyl-anilin, ortheir derivatives e. g. chloro-methyl-s'ulfoor carboxy derivatives,meta-ethyl oxyphenyl para tolylamin, para tolyl-alpha naphthylamin,para-xylidin, etc.

The condensation can also be carried out in another manner e. g. in asolution of sodium acetate.

The oxidation can be carried out with other oxidizing agents 0. g. withnitric acid,

fuming sulfurlc acid, nitro compounds, etc.

I claim I The herein describeddyestufi's obtainable fromformaurin-di-carboxylie acids and aromatic amin's, which dyestufis aredark powders soluble in dilute caustic soda lye generally with a reddishcolor,.dyeing wool from acid baths generally from red to blue shadeswhich can be chromed after dyeing, substantially as described.

In testimony whereof I have. hereunto set my hand in the presence of twosubscribing witnesses.

MAX. WEILER. [n.s] VVitne'sses:

- O'r'ro Komc,

C AS.- J. WRIGHT.

